U-bolt and method of making the same



Mardi 7, H. Q ELLlSQN 1,900,049

u-EoLT AND METHOD oE MAKING THE SAME Filed Marchle, 195o 4 sheets-sheet 1 Sme/nto@ y /ffi 5% E1, MEM/W4 W# mm "n F@ Q R \N NN NN \\.IJS` x mw Q\\`1`.\\ n" m F f C .1 E O O En .M f Q S MM sw mw Nh ...Hu EN @MN L E l--- :Lf: I Q 1| Mardi 7, 1933. I Q ELLlSON 1,900,049

' -BOLT AND METHOD OF MAKING THE ASAME Filed March 19, 1930 4 Sheets-Sheet 2 MalCh 7, 1933. ll| (1;, ELLlS'ON 1,900,049

U-BoLT AND METHOD oF MAKING THE SAME Filed March 19, 1930 4 sheetssheet 5 lJ/ v an f- 535 J3 March 7, 1933.

AND METHOD oF MAKING Filed March 19, 1930 eeeeeeeeeeee t 4 Patented Mar. 7, 19.33

HARRY c. RIi-Lrsoiv, orY LAKEWOOD, R10, iissrenoa4 RRRURLIC s'rnnt ooRioRAfrIoN, .a comorten-.Laoisv :or NRW JERSEY U-nonT AND'MRTHOD or MAKING l'man SAME y Application inea-*Maren 19, 1930; serial No.

This invention relates to U-bolts such as are vused in large quantities for fastening the springs of automobiles to the axles, and to a process of making them. v.

Heretoforetwo distinct types of U -bolt have been in generaly use, namely, a drop (forged U-bolt and a` U-bolt made .from plain round steel. The first type-a drop .forged bolt was better in some respects but was far more expensive to manufacture. Inf the second 'typea line contact only was obtained between the U-bolt and the spring. In order to obtain a better contact between the U-bolt and the spring, the stock was first flattened intermediate its ends and then bent into a` U, thus forming a bolt having a flat bight portion and cylindrical i legs; In corners were the weakest part of thebolt, due to the sharp angular bends between the bight portion and the legs. Thus, in orderto have `suflicient metal at the corners to givev vthe requisite strength, it was necessary to have far more metal-and strengthin the bight portion and legs than was needed." f The principal object of this invention is to produce a U-bolt from plain round stock'having a greater crosssectional" area .at the corners than elsewhere, thereby'to give it the requisite strength at the 'corners without its having unneeded strength-and metal-ein the bightV portion and legs.

Another object'of the invention is to improve manufacturing efliciencyV in the production of U-bolts of the particularly supe-A rior design disclosed herein. I

A further object of the invention is to providel a processwwhich will enable the performance of a plurality of operations on the stock from which the U-bolt'is to be made with only one heating of such stock. l

In the drawings Fig. 1 is a schematic plan view of an improved bolt making machine for carrying out my improved process; Fig. 2 is a schematic vertical section therethrough F ig. 3 is an elevation of my improved U-bolt; Fig. 4 is aplan view ofthe U-bolt of Fig. 3 before the same has'been bent'to U shape and threaded; Fig. 5 is a vertical section; in detailV both these forms theV beted portionsv of section taken onv line 6 6 of Fig. 5; Fig.7is a horizontal` section corresponding to 4that* Lof Fig. 6 but showing the dies in closed position;

.Fig 8 is a horizontal section on line 8-8V of Fig. 5 and Fig.v9. isa horizontal section on line 9-9 of Fig. 5. Y i

In the drawings the numeral 10 indicatesV a'base upon which arel carried the dies, and actuating mechanism of a machine employed in.y .carrying out my improved process. Mounted on s'aid'base in suitable bearings is a crankshaft 11 havingl a crank portion 12; Suit-ably journaled on the crank portion 12 is a connecting rod 13 which is pivotally connected as `at 14 to a cross head 15.. A suitable pulley. 16 is provided for the purpose of driving the cross head 15. A suitable plunger 17 is'removably secured to the cross head 15 by means of any suitable clampingV device 18 and adapted to cooperate with a set of:

sliding dies, indicated generally by thek numeral 19, in a manner hereinafter vto bede,- scribed. The dies l19 are received in. rab-` the base of the frame, suitably protected against wear by wearplates 20 and held clamped in such rabbeted' portions by clamps 21, secured by suitable bolts 22. Attached in any suitable manner to ,the crosshead 15 is a member 23 to which is piv-V otally mounted at 24 a link 25. Pivotally mounted on the'frame' at 26 is a link 27 to which is pivotally connected at 28 a bell crank, having arms 29 and 3() extending from the pivot point 28'and connected tothe link 25 and aslide 31 at 32 and 33 respectively. The cross head 15 works 'between suitable guide plates 34 and 35, while the slide 31` works between similar guide plates 36 and 37. The slide 31 has'an angular face 38 whichcooperates with a die clamping slide 39which may also be termed a'movable ldie since one-half of the dies 19 is 'lixedly car-- ried thereby. Asuitable wearfplate 40 is positioned betweenthe wedging face 38 of the slide 31 and the wedging face 41 of the movable ydie 39. The slide 31 is provided with a suitable slot 42 which cooperateswithv a similar slot 43 in the movable die39 to receive a key 44 which serves to retract the movable die 39 when the slidek 31 is retracted.

STATES, 'PATENT .ortica g, I

Suitable guides and wear plates are provided to receive the movable die 39.

From the foregoing, it will be observed that upon the beginning of the operative cycle due to the rotation of the pulley 16, the movable die 39 will be forced rapidly into clamping engagement with the fixed die and due to the toggle action of the cooperating toggles formed by the bell crank lever and links 25 and 27 which cooperate therewith, a dwell will be produced holding the dies in clamped position before, during, and after the operative stroke of the plunger 17.

The set of dies hereinbefore referred to generally by the numeral 19 are shown in detail in Figs. 5 to 9 inclusive.l In these dies, I provide a pair of main blocks and 51 surrounded by suitable wear plates and held in rabbeted portions in thev main frame 10 and movable die 39 respectively, being clamped as already mentioned by the clamps 21 to prevent upward movement out of the frame. In the lower portion of the blocks 50 and 51 are a pair of sliding die blocks 52 and 53 constrained against any motion eX- cept longitudinal by the blocks 50 and 51 and the keys 54 which connect them with the blocks 50 and 51 as best seen in Fig. 5. These blocks 52 and 53 are not continuous but made up in sections 52a, 52h, 52c and 53a, 53b and 53". Of these sections 52C and 53c are held in fixed relation to the blocks 50 and 51 respectively, while the other sections are movable longitudinally of said blocks. The slidable sections are tensionally constrained to operate by reason of coil springs 55 and 56 between the sections 52b and 52C and the sections 52a and 52", respectively. The construction of the complementary half of these dies involving sections 53a, 53b and 53C are identical and need not be described. Each of the sections 52a, 52b and 520 and 53a, 53b and 53c are drilled and countersunk whereby' bolts 57 and 58 may extend through sections 52a, 52c and 53a, 53c respectively, and be threaded in sections 52b and 53b passing through the central opening of the springs 55 and 56 respectively. The sections 52C and 53V are held in fixed position with respect to the blocks 50 and 51 by means of set screws 59 and 60 respectively. Each of the sections 52C and 53c has a semi-circular counterbored portion 6l, 62 provided for the purpose of y receiving the nose of a pair of tongs 63 as hereinafter set forth. A stock gauge 64 cooperates with the dies to position the bolt forming stock 65 with respect t0 the dies. This stock gauge is carried by the frame 10 and moves into gauging position and remains there until the punch 17 approaches the movable dies and it moves out of the path of the punch. lThe mechanism for accomplishing this motion of the stock gauge is conventional and it is believed unnecessary to go into the same any more fully.

Also carried by the blocks 50 and 51 above the sliding dies just described is a pair of longitudinally fixed dies 66 and 67. These dies are held firmly in position by means of set screws 68 and 69. The shapevof these dies as shown best inFig. 8 is such as to flatten the stock to the shape shown in Fig. 4.

Above the dies 66 and 67 is a set of bending dies consisting of a block 70 carried in the block 50 and having grooves 71 and 72 in its edges which form eXtensions'of grooves 73 and 74 in the block50, the groove 73 communicat'ing with enlarged drilled portions 74a, 74 which is adapted to receive the tongs 63. Carried by the block 51 and held in position therein by means of set screw 7 5, is a die member 76 whichvis adapted to with the die member 70 to perform the bending operation. i

Suitable controls such as electric or compressed air 0r any-other suitable type will be provided wherebythe operator may'conveniently causethe crank shaft l11 to be set in motion or stopped at will.

An especially important 'feature of this machine is the positioning of the three types of dies just described, one above the other.

Operation When the pulley 16 is rotated, a reciproeating motion is imparted to the cross head 15 from which motion is transmitted to the dies 19 in two ways. The slide 31, driven by the toggle mechanism from the member 23 causes reciprocating motion of the slide or movable die 39 in. a direction at right angles thereto. Due to the toggle effect, adwell is'produced in the motion of the movable die 39 when the same is moved into gripping relation with the fixed die carried by the base 10 whereby the movable and fixedl dies will grip the stock therebetween before, during and after the plunger 17 has operatedto squeeze the sliding die sections 52a, 52 b and 53, 53b into close contact with each other and the sections 52c and 53. This motion occurs once for each revolution of the crank shaft, and the stock gauge 64 is moved into alignment with the stock receiving portions of the dies before the plunger 17 is moved into operative relation thereto and said stock gauge is moved out of the path of the plunger 17 before the same can move into contact therewith. The above cycle is repeated each time the pulley 16 rotates irrespective of whether any stock is present between the dies to be operated upon or in which of the three superposed dies the stock happens tobe received.

Pro cess My improved process, in connection with which the above described machine is employed, is designed for the production of U- bolts illustrated in Figs. 3 and 4. As will be seen, these U-bolts consist of two threaded cooperate bolts connected by a bight portion andhaving an eXtrayamount of -metal the bends or corners for. the purpose of strengthening the bolt. VIn carrying out my process, a predefk termined length of stock is heated to the desiredworlringtemperature by the use 'of a heating means placed comparatively close to the machine. `vThe ,heated` stock at properl temperature is withdrawnfr'om the heating means by the use of a pairof tongs 63, 'shown schematically in the drawingsL- The stoel; is inserted in the lowermost or sliding dies, best illustrated inflige. 6 and 7, and pushed bachl until it contacts the stock gauge Gil. After the stock has been Acaused to contact the stock gauge, the tongs are pushed against the same and allowed to slide thereon until the nose of the tongs contacts theshoulders 6lEL ofthe counterbored portion 6l of the die sections 52 and 53C. rlhe crank shaft is then. set into motion, whereupon the movable die 39 moves into gripping relation with the fixed die and the blocks 52 and 53 grip the stock. `After the stool; is gripped, the stock gauge 64 moves to one side and the plunger 17 comes into contacting engagement with the sections 52 and 53a, whereupon the sliding die sections are constrained to move from the position shown in Fig. 6 to that shown in Fig. 7, producing bulges A and B in the stock, which bulges are to supply the extra'metal for the corners or bends of the U-bolt. rlhis having been accomplished, the tongs are caus d to retain their grip on the stock after the dies have opened and thestocl; is then moved upwardly (see Fig. 5) into registration with the dies 66 and 67 where it held during the next cycle of the machine. At this-stage the position of the stock is gauged by pushing'the nose of the tongs against the inner surface 66a of the counterbored portion (56h of the dies 66, 67. During this operation the stock is formed as shown in Figs. l and 8, ready for the bending operation. It will be observed that the central portion of the bolt is flattened and that eXtra metal is introduced at the corners due to the bulges A and B formed in the first operation of the machine. When the machine has completed thesecond cycle, the stock will be moved upwardly intoy engagement with the bending die O, .76 and its positiongauged by means of the tongs as before. As shown in Fig. 9, the stock is bent to final form and the only further operation required is the necessary cooling or tempering operation and threading ofthe two arms of the Uebolt.

It will be evident from theforegoing that with a small amount of practice an operator will be able tov put a bolt through all the steps of the process fromA that of a straight piece of stock to the final form shown in Fig. 9 with one heating and that very rapid production will be made possible.

While I have illustrated the preferred manner of carrying invention into effect, it is obvious that certain changes may be made therein without departing from the inn vention, and I wish it understood .that I am limited only in accordance with the appended claims.

'Having thus I claim is:

described vmy invention, what i l. Thezmethod of producing U-boltscom-`` prising upsetting a bar of stock of predetermined'l lengthat two spaced points intermediate the ends` thereof, thereby-increasing `the cross sectional area at said points, forming the bar to provide two..cylindrical end portions, a flatv intermediate-'portion and connecting portions between the cylindrical 4end portionsy andthe flat intermediate portion at said points of greater cross sectional area,vv

bending the bar at the points of greater cross sectional area to form a U so that the corners between the bight/portion and the legs will be of greater cross sectional area than the bight portion or legs. f

M2. Themethod of producing U-bolts come;

prising upsetting a` barv of stock of predetermined length at two spaced points intermediate the ends thereof, thereby increasing the cross sectional area at said points, ilattening the upset portions of greater cross sectional area and the portion therebetween with no appreciable elongation, bending vthe area to form a U so that the corners between the bight portion and the legs will beA of greater cross sectional area than .the bight portion or legs.

3. The method of producing Ufbolts comprising upsetting a bar of stockA of predetermined length at two spaced points intermediate lthe ends thereof, thereby increasing the cross sectional area at said points, flattening the upsetI portion of greater cross sectional' varea and the portion therebetween by squeezing said portions between a flat die and-,a frusto-pyramidal die thereby-spreading the said portions laterally without elongation,v

bending the bar at the points of greater cross sectional area to form a U so that the corners between the bight portion and the legs will be'of greater cross sectional area than the bight portion or legs.

bar 'at the pointsV of greater cross sectional v l. The method of producing rUv-bolts com- Y greater cross sectional area to form a U so that the corners between the bight portion fifi and the legs will be of greater cross sectional area than the bight portion or legs.

5. The method of producing U-bolts comprising upsetting a bar of stock of predetermined length at two spaced points intermediate the ends thereof, thereby increasingV the cross sectional area at said points, then flattening the upset portions ofvgreater cross sectional area and the portion therebetween, then bending the bar at the vpoints of greater cross sectional area to provide a pair of legs and a bight portion, the upsetting, flattening and bending operations being such that the Vcross sectional area of the bolt at the r corners thereof will be greater than the cross sectional area ofthe bolt elsewhere.

G. The method of producing U-bolts comprising upsetting a bar of stock of predetermined length at two spaced points intermediate the ends thereof, thereby increasing the cross sectional area at said points, forming the bar to provide two cylindrical end portions, a flat intermediate iportion and connecting portions between the cylindrical end portions and the Hat intermediate portion at said points of greatery cross sectional area, bending the bar at the points of greater cross sectional area to form a U so that the corners between the bight portion and the legs will be of greater cross sectional area than the bight portion or legs, the upsetting, Hatten-v ing and bending operations being carried out with but one heating of the stock and in such rapid sequence that the last step is performed while the stock is still at a satisfactory working temperature.

7. A U-bolt of the character described com- )rising a bight portion, a pair of legs extending an angle thereto, one at each end thereof, and corners between the bight portion and legs of greater' cross sectional area than the bight portion or legs, the said corners being formed b-y upsetting two spaced points. in a bar of stock to increase the cross sectional area at these points and then bending the bar at these peints of greater cross sectional area to form a U.

8. A U-bolt of the character described comprising a bight portion rectangular in cross section, a pair of cylindrical legs extending at an angle thereto, one at each end thereof, and corners between the bight portion and legs rectangular in cross section and of greater cross sectional area. than the bight portion or legs, the said corners being formed by upsetting two spaced points in a bar of stock to increase the cross sectional area at these points and then bending the bar at these pointsl of greater cross sectional area to form a U.

9. A U-bolt of the character described comprising a bight portion rectangular in cross section, a pair of legs extending at an angle thereto, one at each end thereof, and corners l between the bight portion and legs rectangusignature.

HARRY C'. ELLISON.

MII 

